Apparatus comprising rotatable shafts or the like



Jan. 22, 1963 T'. PATERSON ETAL 3,074,625

APPARATUS COMPRISING ROTATABLE SHAFTS OR THE LIKE Filed May 2, 1960 2 Sheets-Sheet 1 i c 27 I S: /2 17 2d Z2 v 21 0? l l rura v11 zln lrrax altu Jan. 22, 1963 'r. PATERSON ETAL 3,074,625

APPARATUS COMPRISING ROTATABLE SHAFTS OR THE LIKE Filed May 2, 1960 2 Sheets-Sheet 2 a n/Am;

United States. Patent 3,074,625 APPARATUS COMPRISING ROTATABLE SHAFT S OR THE LIKE Thomas Paterson, Pinner, and Alan Cecil Uttin, Barnet, England, assignors to Simms Motor Units Limited, London, England, a British company Filed May 2, 1960, Ser. No. 25,987 Claims priority, application Great Britain May 8, 1959 4 Claims. (Cl. 230-206) The invention relates to fuel injection pumps and other apparatus comprising rotatable shafts or the like.

The invention provides a fuel injection pump, or other apparatus, comprising an enclosure containing at least part of a rotatable camshaft, crankshaft or the like, means for supplying a lubricating liquid to the enclosure, and an outlet from the enclosure for excess of the lubricating liquid, in which apparatus the excess liquid is caused to flow out through the outlet by action of the shaft on the liquid as the shaft rotates.

Preferably the said outlet comprises a passage leading from the enclosure, which outlet passage extends upwardly out of the enclosure and leaves the enclosure at a position above the level which the surface of the lu bricating liquid assumes when the shaft is not rotating. Preferably the axis of the shaft is substantially horizontal, the said level of the lubricating liquid is below the axis of the shaft, and the outlet passage leaves the enclosure at a position higher than the axis of the shaft.

A specific construction of a fuel injection pump embodying the invention will now be described by way of example and with reference to the accompanying drawings, in which:

FIGURE 1 is a sectional view of the pump on the line 11 of FIGURE 2, and

FIGURE 2 is a side view of the pump, partly in section.

In this example the fuel injection pump includes plungers 11 reciprocated in barrels 12 by means of tappets 9 and earns 13 forming part of a camshaft 14. The camshaft 14 rotates in the direction indicated by the arrow 10 and is contained within an enclosure provided as a lower chamber 15 of the pump casing 16. The casing 16 also forms an upper chamber 17 which contains the plungers and barrels.

When the pump is running a certain amount of fuel oil leaks away between each plunger and its barrel and falls from the upper chamber 17 into the lower chamber 15 through drain holes 18 and tappet bores 20 formed in the web 19 separating the upper and lower chambers.

An oil outlet passage is provided which has a portion 21 extending upwardly through the casing 16 from the lower chamber 15 and communicating with a horizontal portion 22 through a banjo screw 23 retaining a banjo connector 24 leading to a pipe 25. The portion 21 of the passage leaves the chamber 15 at a position higher than the level of the axis of the camshaft.

When the camshaft 14 rotates, it causes a fraction of the oil in the lower chamber 15 to flow out through the outlet passage 21, 22 and the connector 24 to the pipe 25. It is believed that the oil is so caused to flow out through the outlet by reason of oil being thrown against the wall of the chamber as the camshaft rotates.

The structure is arranged to be such (e.g. the size and position of the passage 21, 22 are so chosen) that the rate of escape of oil through the outlet passage 21, 22 is substantially equal to the rate of entry of oil into the chamber 15, so that the amount of oil in the chamber 15 remains approximately the same as the amount which is initially present therein before the pump starts to run i.e. the amount which fills the chamber up to the level 26 Patented Jan. 22, 1963 when the camshaft is not rotating, that level being well below the lower end of the outlet passage 21 and, in this example, below the axis of the camshaft 14. The desired amount of oil is thus maintained in the chamber 15, being an amount adequate to lubricate the camshaft without flooding.

An inspection cover 27 is provided for the upper chamber 17. A bore 28, which is involved in forming'the portion 21.0f the oil outlet passage, is closed by a plug 29.

The invention is not restricted to the details of the foregoing example. For instance the pump may be designed for the camshaft to rotate in the opposite direction, but in that event no change is necessary in the position of the oil outlet passage 21, 22. The invention may be applied to apparatus other than fuel injection pumps, employing camshafts, crankshafts or like shafts.

We claim:

1. A fuel injection pump comprising an enclosure, a rotatable camshaft including cam means, at least part of which camshaft is contained in the enclosure, pumping means operated by the said cam means for pumping fuel, which pumping means include leakage means for supplying fuel oil from said pumping means to the enclosure while the pump is operating to lubricate the camshaft, and an outlet from the enclosure for excess of the fuel oil, the said outlet being spaced above the level which the surface of the fuel oil assumes when the pump has stopped, said enclosure being imperforate below the level of the outlet, and said camshaft constituting excess fuel oil removal means, the excess fuel oil being removed from the enclosure through the outlet by the action on the fuel oil of the camshaft as the camshaft rotates.

2. A fuel injection pump comprising an enclosure, a rotatable camshaft including cam means, at least part of which camshaft is contained in the enclosure, pumping means operated by the said cam means for pumping fuel, which pumping means include leakage means for supplying fuel oil from said pumping means to the enclosure while the pump is operating to lubricate the camshaft, an outlet passage from the enclosure for excess of the fuel oil, which outlet passage leaves the enclosure at a level above the level which the surface of the fuel oil assumes when the pump has stopped and turns downwardly outside the enclosure, the said enclosure being imperforate below the level at which the outlet passage leaves the enclosure, said camshaft constituting excess fuel oil removal means, the excess fuel oil being removed from the enclosure through the outlet passage by the action on the fuel oil of the camshaft as the camshaft rotates.

3. A fuel injection pump comprising an enclosure, a rotatable camshaft including cam means, at least part of which camshaft is contained in the enclosure, pumping means operated by the said cam means for pumping fuel, leakage means for supplying fuel oil from said pumping means to said enclosure while said pump is operating to lubricate said camshaft, the said leakage means being included in said pumping means, and an outlet from said enclosure for excess of the fuel oil, the said outlet being spaced above the level which the surface of the fuel oil assumes when said pump has stopped, the said enclosure being imperforate below the level of said outlet, and excess fuel oil removal means constituted solely by said camshaft, the excess fuel oil being removed from the enclosure through the outlet by the action on the fuel oil of said camshaft as the camshaft rotates.

4. A fuel injection pump comprising an external casing, an enclosure formed in the casing, a rotatable camshaft including cam means, at least part of which camshaft is contained in the enclosure, pumping means operated by the said cam means for pumping fuel, leakage means for supplying fuel oil from said pumping means to said enclosure while said pump is operating to lubricate said camshaft, the said leakage means being included in. the pumping means, an outlet passage from said enclosure for excess of the fuel oil, which outlet pas:

sage is located in the enclosure at a level above the level which the surface of the fuel oil assumes when said pump has stopped, said outlet passage. leading through said casing and turning downwardly outside said casing, said enclosure being imperforate belowthe level of said outlet. passage and excess fuel oil removal means constituted solely by said camshaft, the excess fuel oil being re moved from the enclosure through said outlet passage by the action on the fuel oil of said camshaft as the camshaft rotates.

References Cited in the file of this patent UNITED STATES PATENTS 1,071,068 Maranville Aug. 26, 1913 2,126,985 Buckwalter Aug. 16, 1938 2,188,859 Edwards Jan. 30, 1940 2,285,754 Money June 9, 1942 10 2,658,458 Micolls Nov. 10, 1953 FOREIGN PATENTS 645,262 Germany Apr. 29, 1937 

4. A FUEL INJECTION PUMP COMPRISING AN EXTERNAL CASING, AN ENCLOSURE FORMED IN THE CASING, A ROTATABLE CAMSHAFT INCLUDING CAM MEANS, AT LEAST PART OF WHICH CAMSHAFT IS CONTAINED IN THE ENCLOSURE, PUMPING MEANS OPERATED BY THE SAID CAM MEANS FOR PUMPING FUEL, LEAKAGE MEANS FOR SUPPLYING FUEL OIL FROM SAID PUMPING MEANS TO SAID ENCLOSURE WHILE SAID PUMP IS OPERATING TO LUBRICATE SAID CAMSHAFT, THE SAID LEAKAGE MEANS BEING INCLUDED IN THE PUMPING MEANS, AN OUTLET PASSAGE FROM SAID ENCLOSURE FOR EXCESS OF THE FUEL OIL, WHICH OUTLET PASSAGE IS LOCATED IN THE ENCLOSURE AT A LEVEL ABOVE THE LEVEL WHICH THE SURFACE OF THE FUEL OIL ASSUMES WHEN SAID PUMP HAS STOPPED, SAID OUTLET PASSAGE LEADING THROUGH SAID CASING AND TURNING DOWNWARDLY OUTSIDE SAID CASING, SAID ENCLOSURE BEING IMPERFORATE BELOW THE LEVEL OF SAID OUTLET PASSAGE AND EXCESS FUEL OIL REMOVAL MEANS CONSTITUTED SOLELY BY SAID CAMSHAFT, THE EXCESS FUEL OIL BEING REMOVED FROM THE ENCLOSURE THROUGH SAID OUTLET PASSAGE BY THE ACTION ON THE FUEL OIL OF SAID CAMSHAFT AS THE CAMSHAFT ROTATES. 